Lysates were clarified from sonicated nuclei and protein-DNA complexes were isolated with antibody. ChIP-Seq libraries were prepared according to the manual of VAHTSTM Universal DNA Library Prep Kit for Illumina® V2 (ND606). Briefly, DNA was end-repaired using End Prep Mix 3, ligated with index-contained adapters using Rapid DNA ligase in Rapid Ligation buffer, amplificated using PCR Primers and Amplification Mix for libraries. The library fragments of ~350 bp (insert plus adaptor and PCR primer sequences) were isolated with Agencourt® AMPure® XP (Beckman Coulter®). Library DNAs were sequenced on an Illumina HiSeq platform